1. Field of the Invention
The present invention relates generally to flush valves by which sand or gravel may be quickly and efficiently removed from piping associated with a center pivot irrigation system. Such flush valves, when moved to an open position, provide a fully open port which enables rapid discharge of water for flushing all sand and gravel from the irrigation piping in a very short period of time.
2. Description of the Prior Art
Center pivot irrigation systems are well known and include an elongated elevated water supply pipe rotatably connected at one end to a well and pump unit to supply pressurized water into the pipe. The pipe is supported by a plurality of spaced, ground engaging driven elements, such as wheels, which transport the pipe in a generally horizontal position around a circular path about a center pivot formed by the well and pump unit. A plurality of generally vertical spray pipes depend from the supply pipe, and nozzles at the lower ends of the spray pipes discharge irrigation water adjacent crop level. The elevated supply pipe usually includes a manually operated, elevated end valve which can be opened to enable sand or gravel to be flushed out of the elevated pipe when in open position. Depending upon the quantity of sand and gravel entrained in the irrigation water, the end valve is either left open continuously or manually opened periodically to flush sand and gravel out of the elevated pipe.
The following United States patents relate to various types of valve structures:
While the above patents disclose various types of ball valves, including cam operated ball valves, none disclose a flush valve especially suited for flushing sand and gravel from the piping associated with center pivot irrigation systems. These prior patents also do not disclose an automatic timer controlled, solar powered flush valve located at the lower end of a vertical pipe for connection to an outer end portion of a center pivot elevated irrigation water supply pipe. Further, the prior patents do not disclose a valve that provides a fully opened port and is cam operated between a closed and open position to enable rapid discharge of the water and any entrained sand or gravel which enables the valve to be left open only for a short time, thus saving irrigation water while still enabling sand and gravel to be efficiently flushed from the irrigation system.
The present invention is a timer controlled, solar energy powered, cam operated ball valve which can quickly and efficiently flush sand and gravel from an elevated center pivot irrigation water supply pipe when the ball valve is moved to open position and quickly terminate the discharge of flushing water when the valve is moved to closed position. The automatic ball valve of the present invention is preferably located vertically at the lower end of a down pipe which is connected at its top adjacent the outer end of the irrigation water supply pipe.
The ball valve of the present invention includes a vertical housing which is connected to the lower end of the down pipe preferably by screw threading or the like. The ball valve and ball valve seat are oriented so that gravity and water pressure in the irrigation system will bias the ball valve towards open position. A rotatably driven cam engages the ball valve in opposed relation to the force exerted by gravity and water pressure to retain the ball valve;closed. Rotation of the cam permits the ball valve to move downwardly to open position and upwardly to close position, all in response to an automatic timer control. The cam engaging the ball valve is driven by a solar power unit which includes an electric motor powered from a battery that is charged by an upwardly facing solar power panel. The solar power unit is preferably located in spaced relation to the discharge port for the valve. The discharge port has a cross-sectional area at least generally equal to the cross-sectional area of the down pipe to enable rapid flow of irrigation water out of the down pipe to efficiently and quickly flush sand and gravel from the irrigation system.
An object of the present invention is to provide an automatic solar powered flush valve for center pivot irrigation systems which is timer controlled.
A further object of the present invention is to provide a solar powered flush valve for center pivot irrigation systems which includes a rapidly opening and closing ball valve oriented below a downwardly facing ball valve seat with an operating cam engaging the ball valve for opening and closing the valve.
A still further object of the present invention is to provide an automatic flush valve for center pivot irrigation systems which is driven by an electric motor powered by a rechargeable battery that is recharged by an upwardly facing solar panel located adjacent the discharge port of the valve.
Another object of the present invention is to provide a flush valve for center pivot irrigation systems which is located at the lower end of a down pipe adjacent the outer end of the elevated supply pipe of the center pivot irrigation system.
Yet another object of the present invention is to provide a solar powered flush valve for center pivot irrigation systems which includes a sealed housing to assure maintenance free operation for extended time periods with the flush valve including a ball valve moved vertically in response to rotation of an eccentric powered by a gear motor with the motor being powered by a battery that is charged by a solar panel.
Still another object of the invention is to provide a flush valve for center pivot irrigation systems which is timer controlled with the valve open and valve closed time cycles being selected from a preset large number of available cycles.
A still further object of the present invention is to provide a solar powered flush valve which includes a vertical valve housing provided with a discharge port having a cross-sectional discharge area generally equal to the cross-sectional area of the down pipe supporting the valve and connected to the elevated water supply pipe of the center pivot irrigation system.
Yet another object of this invention to be specifically enumerated herein is to provide a solar powered flush valve for center pivot irrigation systems in accordance with the preceding objects and which will conform to conventional forms of manufacture, be of simple construction and easy to use so as to provide a device that will be economically feasible, long lasting and relatively trouble free in operation.
These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout.